The attempted Christmas Day bombing of a US airliner was a potentially disastrous "screw up" by the intelligence community, President Barack Obama said as he vowed urgent action to tighten air security, yesterday.

Sharpening his tone as he sought to limit political fallout over the intelligence breakdown, Mr Obama said spy agencies had enough information to uncover the December 25 plot to blow up a Detroit-bound flight from Amsterdam but failed to "connect those dots."

On Mr Obama's first full day back from his Hawaii vacation, he faced the challenge of spotlighting national security - suddenly pushed to the top of his agenda - while not looking distracted from other pressing public concerns like reducing double-digit US unemployment.

"We have to do better and we will do better. And we will do it quickly," Mr Obama said after a two-hour meeting with his national security team to discuss what he has called "human and systemic failures" in the Christmas Day incident.

Mr Obama used his sharpest language behind closed doors, telling more than two dozen security chiefs gathered in the Situation Room, "This was a screw-up that could have been disastrous," according to the White House.

"We dodged a bullet but just barely," the White House quoted him as telling the security chiefs. "It was averted by brave individuals not because the system worked, and that is not acceptable."

Passengers and crew subdued the Nigerian bomb suspect as he tried to detonate explosives sewn into his underwear.

Nicknamed "No Drama Obama" for his normally unflappable style, Mr Obama was on the defensive after security lapses allowed the Nigerian man with alleged links to Yemen-based al Qaeda operatives to board the Northwest Airlines flight.